Go to the Tenable Downloads page and select the installer that matches your operating system (Windows, Linux, or macOS).
If you need to test the full commercial version, Tenable offers a 7-day free trial of Nessus Professional, which includes unlimited IP scanning and advanced reporting. Step-by-Step: How to Get Your Free Activation Code
Everything You Need to Know About Getting a Nessus License Key for Free nessus license key free
Run the installer and then access the Nessus interface through your browser at https://localhost:8834 .
Visit the official Nessus Essentials registration page. You will need to provide your first name, last name, and a valid email address. Go to the Tenable Downloads page and select
Check your inbox for a message from Tenable. This email will contain your unique Activation Code (also called a license key).
Tenable provides several "no-cost" options depending on your specific use case: Visit the official Nessus Essentials registration page
This is the primary way for home users and hobbyists to get a free license. It is designed for education and personal use and allows you to scan up to 16 IP addresses .